Merge branch 'akpm' (Andrew's patch-bomb)

Merge Andrew's first set of patches:
 "Non-MM patches:

   - lots of misc bits

   - tree-wide have_clk() cleanups

   - quite a lot of printk tweaks.  I draw your attention to "printk:
     convert the format for KERN_<LEVEL> to a 2 byte pattern" which
     looks a bit scary.  But afaict it's solid.

   - backlight updates

   - lib/ feature work (notably the addition and use of memweight())

   - checkpatch updates

   - rtc updates

   - nilfs updates

   - fatfs updates (partial, still waiting for acks)

   - kdump, proc, fork, IPC, sysctl, taskstats, pps, etc

   - new fault-injection feature work"

* Merge emailed patches from Andrew Morton <akpm@linux-foundation.org>: (128 commits)
  drivers/misc/lkdtm.c: fix missing allocation failure check
  lib/scatterlist: do not re-write gfp_flags in __sg_alloc_table()
  fault-injection: add tool to run command with failslab or fail_page_alloc
  fault-injection: add selftests for cpu and memory hotplug
  powerpc: pSeries reconfig notifier error injection module
  memory: memory notifier error injection module
  PM: PM notifier error injection module
  cpu: rewrite cpu-notifier-error-inject module
  fault-injection: notifier error injection
  c/r: fcntl: add F_GETOWNER_UIDS option
  resource: make sure requested range is included in the root range
  include/linux/aio.h: cpp->C conversions
  fs: cachefiles: add support for large files in filesystem caching
  pps: return PTR_ERR on error in device_create
  taskstats: check nla_reserve() return
  sysctl: suppress kmemleak messages
  ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION
  ipc: compat: use signed size_t types for msgsnd and msgrcv
  ipc: allow compat IPC version field parsing if !ARCH_WANT_OLD_COMPAT_IPC
  ipc: add COMPAT_SHMLBA support
  ...

40 files changed, 408 insertions, 300 deletions

diff --git a/fs/affs/bitmap.c b/fs/affs/bitmap.c
index 6e0be43ef6ef..a32246b8359e 100644
--- a/fs/affs/bitmap.c
+++ b/fs/affs/bitmap.c
@@ -10,30 +10,6 @@
 #include <linux/slab.h>
 #include "affs.h"
 
-/* This is, of course, shamelessly stolen from fs/minix */
-
-static const int nibblemap[] = { 0,1,1,2,1,2,2,3,1,2,2,3,2,3,3,4 };
-
-static u32
-affs_count_free_bits(u32 blocksize, const void *data)
-{
-	const u32 *map;
-	u32 free;
-	u32 tmp;
-
-	map = data;
-	free = 0;
-	for (blocksize /= 4; blocksize > 0; blocksize--) {
-		tmp = *map++;
-		while (tmp) {
-			free += nibblemap[tmp & 0xf];
-			tmp >>= 4;
-		}
-	}
-
-	return free;
-}
-
 u32
 affs_count_free_blocks(struct super_block *sb)
 {
@@ -317,7 +293,7 @@ int affs_init_bitmap(struct super_block *sb, int *flags)
 			goto out;
 		}
 		pr_debug("AFFS: read bitmap block %d: %d\n", blk, bm->bm_key);
-		bm->bm_free = affs_count_free_bits(sb->s_blocksize - 4, bh->b_data + 4);
+		bm->bm_free = memweight(bh->b_data + 4, sb->s_blocksize - 4);
 
 		/* Don't try read the extension if this is the last block,
 		 * but we also need the right bm pointer below
@@ -367,7 +343,7 @@ int affs_init_bitmap(struct super_block *sb, int *flags)
 
 	/* recalculate bitmap count for last block */
 	bm--;
-	bm->bm_free = affs_count_free_bits(sb->s_blocksize - 4, bh->b_data + 4);
+	bm->bm_free = memweight(bh->b_data + 4, sb->s_blocksize - 4);
 
 out:
 	affs_brelse(bh);
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index adb1cd7ceb9b..4bab807227ad 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3342,10 +3342,22 @@ ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size);
 /* super.c */
 int btrfs_parse_options(struct btrfs_root *root, char *options);
 int btrfs_sync_fs(struct super_block *sb, int wait);
+
+#ifdef CONFIG_PRINTK
+__printf(2, 3)
 void btrfs_printk(struct btrfs_fs_info *fs_info, const char *fmt, ...);
+#else
+static inline __printf(2, 3)
+void btrfs_printk(struct btrfs_fs_info *fs_info, const char *fmt, ...)
+{
+}
+#endif
+
+__printf(5, 6)
 void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function,
 		     unsigned int line, int errno, const char *fmt, ...);
 
+
 void __btrfs_abort_transaction(struct btrfs_trans_handle *trans,
 			       struct btrfs_root *root, const char *function,
 			       unsigned int line, int errno);
@@ -3386,6 +3398,7 @@ do {								\
 			  (errno), fmt, ##args);		\
 } while (0)
 
+__printf(5, 6)
 void __btrfs_panic(struct btrfs_fs_info *fs_info, const char *function,
 		   unsigned int line, int errno, const char *fmt, ...);
 
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 502b20c56e84..fadeba6a5db9 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1114,7 +1114,7 @@ void clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 				spin_unlock(&root->fs_info->delalloc_lock);
 				btrfs_panic(root->fs_info, -EOVERFLOW,
 					  "Can't clear %lu bytes from "
-					  " dirty_mdatadata_bytes (%lu)",
+					  " dirty_mdatadata_bytes (%llu)",
 					  buf->len,
 					  root->fs_info->dirty_metadata_bytes);
 			}
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index c5dbd9149679..4da08652004d 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -1241,7 +1241,7 @@ static int __must_check __add_reloc_root(struct btrfs_root *root)
 	if (rb_node) {
 		btrfs_panic(root->fs_info, -EEXIST, "Duplicate root found "
 			    "for start=%llu while inserting into relocation "
-			    "tree\n");
+			    "tree\n", node->bytenr);
 		kfree(node);
 		return -EEXIST;
 	}
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index fa61ef59cd61..8c6e61d6eed5 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -125,6 +125,7 @@ static void btrfs_handle_error(struct btrfs_fs_info *fs_info)
 	}
 }
 
+#ifdef CONFIG_PRINTK
 /*
  * __btrfs_std_error decodes expected errors from the caller and
  * invokes the approciate error response.
@@ -167,7 +168,7 @@ void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function,
 	va_end(args);
 }
 
-const char *logtypes[] = {
+static const char * const logtypes[] = {
 	"emergency",
 	"alert",
 	"critical",
@@ -185,22 +186,50 @@ void btrfs_printk(struct btrfs_fs_info *fs_info, const char *fmt, ...)
 	struct va_format vaf;
 	va_list args;
 	const char *type = logtypes[4];
+	int kern_level;
 
 	va_start(args, fmt);
 
-	if (fmt[0] == '<' && isdigit(fmt[1]) && fmt[2] == '>') {
-		memcpy(lvl, fmt, 3);
-		lvl[3] = '\0';
-		fmt += 3;
-		type = logtypes[fmt[1] - '0'];
+	kern_level = printk_get_level(fmt);
+	if (kern_level) {
+		size_t size = printk_skip_level(fmt) - fmt;
+		memcpy(lvl, fmt,  size);
+		lvl[size] = '\0';
+		fmt += size;
+		type = logtypes[kern_level - '0'];
 	} else
 		*lvl = '\0';
 
 	vaf.fmt = fmt;
 	vaf.va = &args;
+
 	printk("%sBTRFS %s (device %s): %pV", lvl, type, sb->s_id, &vaf);
+
+	va_end(args);
 }
 
+#else
+
+void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function,
+		       unsigned int line, int errno, const char *fmt, ...)
+{
+	struct super_block *sb = fs_info->sb;
+
+	/*
+	 * Special case: if the error is EROFS, and we're already
+	 * under MS_RDONLY, then it is safe here.
+	 */
+	if (errno == -EROFS && (sb->s_flags & MS_RDONLY))
+		return;
+
+	/* Don't go through full error handling during mount */
+	if (sb->s_flags & MS_BORN) {
+		save_error_info(fs_info);
+		btrfs_handle_error(fs_info);
+	}
+}
+#endif
+
 /*
  * We only mark the transaction aborted and then set the file system read-only.
  * This will prevent new transactions from starting or trying to join this
diff --git a/fs/cachefiles/rdwr.c b/fs/cachefiles/rdwr.c
index c0353dfac51f..c994691d9445 100644
--- a/fs/cachefiles/rdwr.c
+++ b/fs/cachefiles/rdwr.c
@@ -919,7 +919,7 @@ int cachefiles_write_page(struct fscache_storage *op, struct page *page)
 	 * own time */
 	path.mnt = cache->mnt;
 	path.dentry = object->backer;
-	file = dentry_open(&path, O_RDWR, cache->cache_cred);
+	file = dentry_open(&path, O_RDWR | O_LARGEFILE, cache->cache_cred);
 	if (IS_ERR(file)) {
 		ret = PTR_ERR(file);
 	} else {
diff --git a/fs/exec.c b/fs/exec.c
index e95aeeddd25c..3684353ebd5f 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -2002,17 +2002,17 @@ static void coredump_finish(struct mm_struct *mm)
 void set_dumpable(struct mm_struct *mm, int value)
 {
 	switch (value) {
-	case 0:
+	case SUID_DUMPABLE_DISABLED:
 		clear_bit(MMF_DUMPABLE, &mm->flags);
 		smp_wmb();
 		clear_bit(MMF_DUMP_SECURELY, &mm->flags);
 		break;
-	case 1:
+	case SUID_DUMPABLE_ENABLED:
 		set_bit(MMF_DUMPABLE, &mm->flags);
 		smp_wmb();
 		clear_bit(MMF_DUMP_SECURELY, &mm->flags);
 		break;
-	case 2:
+	case SUID_DUMPABLE_SAFE:
 		set_bit(MMF_DUMP_SECURELY, &mm->flags);
 		smp_wmb();
 		set_bit(MMF_DUMPABLE, &mm->flags);
@@ -2025,7 +2025,7 @@ static int __get_dumpable(unsigned long mm_flags)
 	int ret;
 
 	ret = mm_flags & MMF_DUMPABLE_MASK;
-	return (ret >= 2) ? 2 : ret;
+	return (ret > SUID_DUMPABLE_ENABLED) ? SUID_DUMPABLE_SAFE : ret;
 }
 
 int get_dumpable(struct mm_struct *mm)
@@ -2111,6 +2111,7 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs)
 	int retval = 0;
 	int flag = 0;
 	int ispipe;
+	bool need_nonrelative = false;
 	static atomic_t core_dump_count = ATOMIC_INIT(0);
 	struct coredump_params cprm = {
 		.signr = signr,
@@ -2136,14 +2137,16 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs)
 	if (!cred)
 		goto fail;
 	/*
-	 *	We cannot trust fsuid as being the "true" uid of the
-	 *	process nor do we know its entire history. We only know it
-	 *	was tainted so we dump it as root in mode 2.
+	 * We cannot trust fsuid as being the "true" uid of the process
+	 * nor do we know its entire history. We only know it was tainted
+	 * so we dump it as root in mode 2, and only into a controlled
+	 * environment (pipe handler or fully qualified path).
 	 */
-	if (__get_dumpable(cprm.mm_flags) == 2) {
+	if (__get_dumpable(cprm.mm_flags) == SUID_DUMPABLE_SAFE) {
 		/* Setuid core dump mode */
 		flag = O_EXCL;		/* Stop rewrite attacks */
 		cred->fsuid = GLOBAL_ROOT_UID;	/* Dump root private */
+		need_nonrelative = true;
 	}
 
 	retval = coredump_wait(exit_code, &core_state);
@@ -2171,15 +2174,16 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs)
 		}
 
 		if (cprm.limit == 1) {
-			/*
+			/* See umh_pipe_setup() which sets RLIMIT_CORE = 1.
+			 *
 			 * Normally core limits are irrelevant to pipes, since
 			 * we're not writing to the file system, but we use
-			 * cprm.limit of 1 here as a speacial value. Any
-			 * non-1 limit gets set to RLIM_INFINITY below, but
-			 * a limit of 0 skips the dump.  This is a consistent
-			 * way to catch recursive crashes.  We can still crash
-			 * if the core_pattern binary sets RLIM_CORE =  !1
-			 * but it runs as root, and can do lots of stupid things
+			 * cprm.limit of 1 here as a speacial value, this is a
+			 * consistent way to catch recursive crashes.
+			 * We can still crash if the core_pattern binary sets
+			 * RLIM_CORE = !1, but it runs as root, and can do
+			 * lots of stupid things.
+			 *
 			 * Note that we use task_tgid_vnr here to grab the pid
 			 * of the process group leader.  That way we get the
 			 * right pid if a thread in a multi-threaded
@@ -2223,6 +2227,14 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs)
 		if (cprm.limit < binfmt->min_coredump)
 			goto fail_unlock;
 
+		if (need_nonrelative && cn.corename[0] != '/') {
+			printk(KERN_WARNING "Pid %d(%s) can only dump core "\
+				"to fully qualified path!\n",
+				task_tgid_vnr(current), current->comm);
+			printk(KERN_WARNING "Skipping core dump\n");
+			goto fail_unlock;
+		}
+
 		cprm.file = filp_open(cn.corename,
 				 O_CREAT | 2 | O_NOFOLLOW | O_LARGEFILE | flag,
 				 0600);
diff --git a/fs/ext2/balloc.c b/fs/ext2/balloc.c
index 1c3613998862..376aa77f3ca7 100644
--- a/fs/ext2/balloc.c
+++ b/fs/ext2/balloc.c
@@ -1444,19 +1444,9 @@ ext2_fsblk_t ext2_new_block(struct inode *inode, unsigned long goal, int *errp)
 
 #ifdef EXT2FS_DEBUG
 
-static const int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
-
-unsigned long ext2_count_free (struct buffer_head * map, unsigned int numchars)
+unsigned long ext2_count_free(struct buffer_head *map, unsigned int numchars)
 {
-	unsigned int i;
-	unsigned long sum = 0;
-
-	if (!map)
-		return (0);
-	for (i = 0; i < numchars; i++)
-		sum += nibblemap[map->b_data[i] & 0xf] +
-			nibblemap[(map->b_data[i] >> 4) & 0xf];
-	return (sum);
+	return numchars * BITS_PER_BYTE - memweight(map->b_data, numchars);
 }
 
 #endif  /*  EXT2FS_DEBUG  */
diff --git a/fs/ext2/ialloc.c b/fs/ext2/ialloc.c
index c13eb7b91a11..8f370e012e61 100644
--- a/fs/ext2/ialloc.c
+++ b/fs/ext2/ialloc.c
@@ -644,6 +644,7 @@ unsigned long ext2_count_free_inodes (struct super_block * sb)
 	}
 	brelse(bitmap_bh);
 	printk("ext2_count_free_inodes: stored = %lu, computed = %lu, %lu\n",
+		(unsigned long)
 		percpu_counter_read(&EXT2_SB(sb)->s_freeinodes_counter),
 		desc_count, bitmap_count);
 	return desc_count;
diff --git a/fs/ext3/balloc.c b/fs/ext3/balloc.c
index 25cd60892116..90d901f0486b 100644
--- a/fs/ext3/balloc.c
+++ b/fs/ext3/balloc.c
@@ -1813,7 +1813,7 @@ ext3_fsblk_t ext3_count_free_blocks(struct super_block *sb)
 	brelse(bitmap_bh);
 	printk("ext3_count_free_blocks: stored = "E3FSBLK
 		", computed = "E3FSBLK", "E3FSBLK"\n",
-	       le32_to_cpu(es->s_free_blocks_count),
+	       (ext3_fsblk_t)le32_to_cpu(es->s_free_blocks_count),
 		desc_count, bitmap_count);
 	return bitmap_count;
 #else
diff --git a/fs/ext3/bitmap.c b/fs/ext3/bitmap.c
index 909d13e26560..ef9c643e8e9d 100644
--- a/fs/ext3/bitmap.c
+++ b/fs/ext3/bitmap.c
@@ -11,19 +11,9 @@
 
 #ifdef EXT3FS_DEBUG
 
-static const int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
-
 unsigned long ext3_count_free (struct buffer_head * map, unsigned int numchars)
 {
-	unsigned int i;
-	unsigned long sum = 0;
-
-	if (!map)
-		return (0);
-	for (i = 0; i < numchars; i++)
-		sum += nibblemap[map->b_data[i] & 0xf] +
-			nibblemap[(map->b_data[i] >> 4) & 0xf];
-	return (sum);
+	return numchars * BITS_PER_BYTE - memweight(map->b_data, numchars);
 }
 
 #endif  /*  EXT3FS_DEBUG  */
diff --git a/fs/ext4/bitmap.c b/fs/ext4/bitmap.c
index a94b9c63ee5c..f8716eab9995 100644
--- a/fs/ext4/bitmap.c
+++ b/fs/ext4/bitmap.c
@@ -11,16 +11,9 @@
 #include <linux/jbd2.h>
 #include "ext4.h"
 
-static const int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
-
 unsigned int ext4_count_free(char *bitmap, unsigned int numchars)
 {
-	unsigned int i, sum = 0;
-
-	for (i = 0; i < numchars; i++)
-		sum += nibblemap[bitmap[i] & 0xf] +
-			nibblemap[(bitmap[i] >> 4) & 0xf];
-	return sum;
+	return numchars * BITS_PER_BYTE - memweight(bitmap, numchars);
 }
 
 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
diff --git a/fs/fat/dir.c b/fs/fat/dir.c
index 6eaa28c98ad1..dc49ed2cbffa 100644
--- a/fs/fat/dir.c
+++ b/fs/fat/dir.c
@@ -35,6 +35,11 @@
 #define FAT_MAX_UNI_CHARS	((MSDOS_SLOTS - 1) * 13 + 1)
 #define FAT_MAX_UNI_SIZE	(FAT_MAX_UNI_CHARS * sizeof(wchar_t))
 
+static inline unsigned char fat_tolower(unsigned char c)
+{
+	return ((c >= 'A') && (c <= 'Z')) ? c+32 : c;
+}
+
 static inline loff_t fat_make_i_pos(struct super_block *sb,
 				    struct buffer_head *bh,
 				    struct msdos_dir_entry *de)
@@ -333,6 +338,124 @@ parse_long:
 	return 0;
 }
 
+/**
+ * fat_parse_short - Parse MS-DOS (short) directory entry.
+ * @sb:		superblock
+ * @de:		directory entry to parse
+ * @name:	FAT_MAX_SHORT_SIZE array in which to place extracted name
+ * @dot_hidden:	Nonzero == prepend '.' to names with ATTR_HIDDEN
+ *
+ * Returns the number of characters extracted into 'name'.
+ */
+static int fat_parse_short(struct super_block *sb,
+			   const struct msdos_dir_entry *de,
+			   unsigned char *name, int dot_hidden)
+{
+	const struct msdos_sb_info *sbi = MSDOS_SB(sb);
+	int isvfat = sbi->options.isvfat;
+	int nocase = sbi->options.nocase;
+	unsigned short opt_shortname = sbi->options.shortname;
+	struct nls_table *nls_disk = sbi->nls_disk;
+	wchar_t uni_name[14];
+	unsigned char c, work[MSDOS_NAME];
+	unsigned char *ptname = name;
+	int chi, chl, i, j, k;
+	int dotoffset = 0;
+	int name_len = 0, uni_len = 0;
+
+	if (!isvfat && dot_hidden && (de->attr & ATTR_HIDDEN)) {
+		*ptname++ = '.';
+		dotoffset = 1;
+	}
+
+	memcpy(work, de->name, sizeof(work));
+	/* see namei.c, msdos_format_name */
+	if (work[0] == 0x05)
+		work[0] = 0xE5;
+
+	/* Filename */
+	for (i = 0, j = 0; i < 8;) {
+		c = work[i];
+		if (!c)
+			break;
+		chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
+					&uni_name[j++], opt_shortname,
+					de->lcase & CASE_LOWER_BASE);
+		if (chl <= 1) {
+			if (!isvfat)
+				ptname[i] = nocase ? c : fat_tolower(c);
+			i++;
+			if (c != ' ') {
+				name_len = i;
+				uni_len  = j;
+			}
+		} else {
+			uni_len = j;
+			if (isvfat)
+				i += min(chl, 8-i);
+			else {
+				for (chi = 0; chi < chl && i < 8; chi++, i++)
+					ptname[i] = work[i];
+			}
+			if (chl)
+				name_len = i;
+		}
+	}
+
+	i = name_len;
+	j = uni_len;
+	fat_short2uni(nls_disk, ".", 1, &uni_name[j++]);
+	if (!isvfat)
+		ptname[i] = '.';
+	i++;
+
+	/* Extension */
+	for (k = 8; k < MSDOS_NAME;) {
+		c = work[k];
+		if (!c)
+			break;
+		chl = fat_shortname2uni(nls_disk, &work[k], MSDOS_NAME - k,
+					&uni_name[j++], opt_shortname,
+					de->lcase & CASE_LOWER_EXT);
+		if (chl <= 1) {
+			k++;
+			if (!isvfat)
+				ptname[i] = nocase ? c : fat_tolower(c);
+			i++;
+			if (c != ' ') {
+				name_len = i;
+				uni_len  = j;
+			}
+		} else {
+			uni_len = j;
+			if (isvfat) {
+				int offset = min(chl, MSDOS_NAME-k);
+				k += offset;
+				i += offset;
+			} else {
+				for (chi = 0; chi < chl && k < MSDOS_NAME;
+				     chi++, i++, k++) {
+						ptname[i] = work[k];
+				}
+			}
+			if (chl)
+				name_len = i;
+		}
+	}
+
+	if (name_len > 0) {
+		name_len += dotoffset;
+
+		if (sbi->options.isvfat) {
+			uni_name[uni_len] = 0x0000;
+			name_len = fat_uni_to_x8(sb, uni_name, name,
+						 FAT_MAX_SHORT_SIZE);
+		}
+	}
+
+	return name_len;
+}
+
 /*
  * Return values: negative -> error, 0 -> not found, positive -> found,
  * value is the total amount of slots, including the shortname entry.
@@ -344,15 +467,11 @@ int fat_search_long(struct inode *inode, const unsigned char *name,
 	struct msdos_sb_info *sbi = MSDOS_SB(sb);
 	struct buffer_head *bh = NULL;
 	struct msdos_dir_entry *de;
-	struct nls_table *nls_disk = sbi->nls_disk;
 	unsigned char nr_slots;
-	wchar_t bufuname[14];
 	wchar_t *unicode = NULL;
-	unsigned char work[MSDOS_NAME];
 	unsigned char bufname[FAT_MAX_SHORT_SIZE];
-	unsigned short opt_shortname = sbi->options.shortname;
 	loff_t cpos = 0;
-	int chl, i, j, last_u, err, len;
+	int err, len;
 
 	err = -ENOENT;
 	while (1) {
@@ -380,47 +499,16 @@ parse_record:
 				goto end_of_dir;
 		}
 
-		memcpy(work, de->name, sizeof(de->name));
-		/* see namei.c, msdos_format_name */
-		if (work[0] == 0x05)
-			work[0] = 0xE5;
-		for (i = 0, j = 0, last_u = 0; i < 8;) {
-			if (!work[i])
-				break;
-			chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
-						&bufuname[j++], opt_shortname,
-						de->lcase & CASE_LOWER_BASE);
-			if (chl <= 1) {
-				if (work[i] != ' ')
-					last_u = j;
-			} else {
-				last_u = j;
-			}
-			i += chl;
-		}
-		j = last_u;
-		fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
-		for (i = 8; i < MSDOS_NAME;) {
-			if (!work[i])
-				break;
-			chl = fat_shortname2uni(nls_disk, &work[i],
-						MSDOS_NAME - i,
-						&bufuname[j++], opt_shortname,
-						de->lcase & CASE_LOWER_EXT);
-			if (chl <= 1) {
-				if (work[i] != ' ')
-					last_u = j;
-			} else {
-				last_u = j;
-			}
-			i += chl;
-		}
-		if (!last_u)
+		/* Never prepend '.' to hidden files here.
+		 * That is done only for msdos mounts (and only when
+		 * 'dotsOK=yes'); if we are executing here, it is in the
+		 * context of a vfat mount.
+		 */
+		len = fat_parse_short(sb, de, bufname, 0);
+		if (len == 0)
 			continue;
 
 		/* Compare shortname */
-		bufuname[last_u] = 0x0000;
-		len = fat_uni_to_x8(sb, bufuname, bufname, sizeof(bufname));
 		if (fat_name_match(sbi, name, name_len, bufname, len))
 			goto found;
 
@@ -469,20 +557,15 @@ static int __fat_readdir(struct inode *inode, struct file *filp, void *dirent,
 	struct msdos_sb_info *sbi = MSDOS_SB(sb);
 	struct buffer_head *bh;
 	struct msdos_dir_entry *de;
-	struct nls_table *nls_disk = sbi->nls_disk;
 	unsigned char nr_slots;
-	wchar_t bufuname[14];
 	wchar_t *unicode = NULL;
-	unsigned char c, work[MSDOS_NAME];
-	unsigned char bufname[FAT_MAX_SHORT_SIZE], *ptname = bufname;
-	unsigned short opt_shortname = sbi->options.shortname;
+	unsigned char bufname[FAT_MAX_SHORT_SIZE];
 	int isvfat = sbi->options.isvfat;
-	int nocase = sbi->options.nocase;
 	const char *fill_name = NULL;
 	unsigned long inum;
 	unsigned long lpos, dummy, *furrfu = &lpos;
 	loff_t cpos;
-	int chi, chl, i, i2, j, last, last_u, dotoffset = 0, fill_len = 0;
+	int short_len = 0, fill_len = 0;
 	int ret = 0;
 
 	lock_super(sb);
@@ -556,74 +639,10 @@ parse_record:
 		}
 	}
 
-	if (sbi->options.dotsOK) {
-		ptname = bufname;
-		dotoffset = 0;
-		if (de->attr & ATTR_HIDDEN) {
-			*ptname++ = '.';
-			dotoffset = 1;
-		}
-	}
-
-	memcpy(work, de->name, sizeof(de->name));
-	/* see namei.c, msdos_format_name */
-	if (work[0] == 0x05)
-		work[0] = 0xE5;
-	for (i = 0, j = 0, last = 0, last_u = 0; i < 8;) {
-		if (!(c = work[i]))
-			break;
-		chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
-					&bufuname[j++], opt_shortname,
-					de->lcase & CASE_LOWER_BASE);
-		if (chl <= 1) {
-			ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
-			if (c != ' ') {
-				last = i;
-				last_u = j;
-			}
-		} else {
-			last_u = j;
-			for (chi = 0; chi < chl && i < 8; chi++) {
-				ptname[i] = work[i];
-				i++; last = i;
-			}
-		}
-	}
-	i = last;
-	j = last_u;
-	fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
-	ptname[i++] = '.';
-	for (i2 = 8; i2 < MSDOS_NAME;) {
-		if (!(c = work[i2]))
-			break;
-		chl = fat_shortname2uni(nls_disk, &work[i2], MSDOS_NAME - i2,
-					&bufuname[j++], opt_shortname,
-					de->lcase & CASE_LOWER_EXT);
-		if (chl <= 1) {
-			i2++;
-			ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
-			if (c != ' ') {
-				last = i;
-				last_u = j;
-			}
-		} else {
-			last_u = j;
-			for (chi = 0; chi < chl && i2 < MSDOS_NAME; chi++) {
-				ptname[i++] = work[i2++];
-				last = i;
-			}
-		}
-	}
-	if (!last)
+	short_len = fat_parse_short(sb, de, bufname, sbi->options.dotsOK);
+	if (short_len == 0)
 		goto record_end;
 
-	i = last + dotoffset;
-	j = last_u;
-
-	if (isvfat) {
-		bufuname[j] = 0x0000;
-		i = fat_uni_to_x8(sb, bufuname, bufname, sizeof(bufname));
-	}
 	if (nr_slots) {
 		/* hack for fat_ioctl_filldir() */
 		struct fat_ioctl_filldir_callback *p = dirent;
@@ -631,12 +650,12 @@ parse_record:
 		p->longname = fill_name;
 		p->long_len = fill_len;
 		p->shortname = bufname;
-		p->short_len = i;
+		p->short_len = short_len;
 		fill_name = NULL;
 		fill_len = 0;
 	} else {
 		fill_name = bufname;
-		fill_len = i;
+		fill_len = short_len;
 	}
 
 start_filldir:
diff --git a/fs/fat/fat.h b/fs/fat/fat.h
index fc35c5c69136..2deeeb86f331 100644
--- a/fs/fat/fat.h
+++ b/fs/fat/fat.h
@@ -217,6 +217,21 @@ static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len)
 #endif
 }
 
+static inline int fat_get_start(const struct msdos_sb_info *sbi,